The feature space based on the L2 and SSIM reconstruction error metrics performed better in the OK and NOK classes separation, although the OK class cluster still overlaps with a part of the NOK data. The results can be seen on the right part of figure REF . The overlapping NOK data are probably from the Not complete class which is expected to show a lower reconstruction error than the other NOK class samples. Surprisingly and unlike in the paper [1]}, the SSIM metric shows a low variance between the OK and NOK class, while the L2 metric seems to better distinguish those classes. It is probable, that the class separation might be increased by adding another reconstruction error metrics.
